Topological Quantum Computing is a promising scheme for achieving general quantum computation. Such schemes store single logical qubits in a lattice of physical qubits, and use quantum measurement and purely classical error correction to preserve the logical qubits in the face of experimental conditions. This permits logical qubits to be preserved for substantially longer than the typical coherence time of the physical qubits.
To achieve this, it is necessary to measure classical ancilla bits and perform a complex classical error correction in times commensurate with the coherence time of the physical qubits. In applications, this may require handling ˜103 physical qubits and measuring an ancilla bit from each of them at ˜106 Hz. However, the data processing required is thus at the scale of gigabits/second, which exceeds feasible processing rates for commercial general-purpose processors.